Pusher airplane



Aug. 6, 1929. c. G. THOMPSON PUSHER AIRPLANE Filed March 17, 1928 3Sheets-Sheet lNVE/VTOR G5. Thom 250m .6 v a U m .-w"\ qr wnnnununwwfi EW 6 5 9 j Aug. 6, 1929- c. s. THOMPSON PUSHER AIRPLANE Filed March 17,1928 3 Sheets-Sheet Aug. 6, 1929. c. G. THomsoN PUSHER AIRPLANE FiledMarch 17, 1928 3 Sheets-Sheet 3 lNVEIww-OR, 67$ 7724/72 6077/.

.UNITED TA ES} Patented Aug. 6, 192 9.

I CARL G.-'rnom so1, or s'r. LOUIS, mssoom. I

IUSHEB E.

Application filed March 17, 1928. Serial no.

maximum stability, such as inherent, static, dynamic, longitudinal,dlrectlonal and lateral; fourth, affording the. maximum of safety inlanding; fiftlnthe provision of airfoils affording the maximum usefuldynamic reaction; sixth, the provision of superposed sweep hackairfoils, each of which is ofless dimension laterally thanlongitudinally and which have a convexed dipping trailing edge, dippingside edges which gradually disap pear toward a convexed leadingedgewhich is the termination of an upwardly curved breast section of each'airfoil; seventh, the provision of an auxiliary, or intermediate rearairfoil having a dipping rearedge and dipping side edges; eighth,positioning of rudders in advance of the a-irfoils; ninth, po sitioningof superposed elevators between the breast portions of the superposedail-foils; tenth. the provision of movable opposed, vertically disposedbooster planes in advance of the auxiliary airfoil; eleventh, thepositioning of the power plant upon the lower airfoil; twelfth, theprovision 'of a pusher propeller; thirteenth, the provision of a'horizontally disposed landing propeller located below thet-railing endportion of thelower airfoil; and,

fourteenth, the provision of a wheel landing ear b 1 A further object ofthe invent-ion the provision of a pusher airplane, whichpossesses'advantages in points of simplicity and efiiciency, and, at thesame time proves itself comparatlvcly inexpensive in cost of manufacture.

With the above and other objects in view,

the invention consists in the novel features of construction.arrangement and combination of parts hereinafter more fully describedand finally pointed out in the claims hereto appended.

Referring to the accompanying drawings forming a part of'thisspecification, wherein like characters of reference denote similar partsthroughout the several views:

PATENT orrlcn;

Fig. 1, is a side elevation of a pusher airplane embodying the'featuresof my-invention. I v

Fig. 2, 1s a transverse vertical sectional View of the a-irplanei' Flg.3, is a trailing end elevation plane.

Fig. 4, is a longitudinal vertical sectional:

elevation ofthe airplane.

Fig. 5, is a top .plan view thereof.

of the air- Fig.6, is a detail of one-of .the landingwheels "auditsconnection with the lower airfoil.

vention, I employ a lower airfoil 1 having a flat dlverglng' bodyportion 2 terminating at opposite ends 1n. reversely curved portions,

so as to provide arear dipping edge portion.-

3, which is given a convex cambered trailing edge 4, and to provide anupwardly'gently curved forward breast portion 5 for, the airfoil. Theflat diverging body portion 2 and the upwardly curved breast portion 5thereof are provided with .the sweep back dipping side edge portions 6having the sweep back edges 7 which merge at their rear ends with Incarrying out the aim ofmy present inthe rear dipping edge portion 3 andthe t-railing' edge 4, respectlvely, and whichside .dipping edgeportions Hpractieally'fade out at the leading edge 8 'of the airfoil 1which is giveifa conveyed camber or curvature, as will be apparent inFig. 5. plan view, the I lower-airfoil 1, as will be apparent from Fig.

1. has a narrow leading edge which sweeps back to a trailing edge. Thelower. airfoil 1 is mounted upon and suitably secured to a pair ofsuitably connected diverging longrons designated 9, the forward ends 10of which are-curved upwardly and forwardly beyond the leading edge 8 ofthe airfoil 1.

Spaced from and disposed above the longr'ons 9 are a pair of suitably.connected upper diverging longrons 11, which'are rigidly eonnccted withthe lower longronsf9 by means of a plurality of suitable supportingstruts 12 to form the frame work of "an open fuselage. The upperlongrons 11 extend be.-

yond the rear ends of the lower longrons 9 V and have their rear endscurved-downwardly, as at 13, and their forward ends curved upwardly, asat 14. The leading ends of the upwardly curved portions 14 of the "upperlon-.

grons 11 are disposed above and to the'rear of the leading ends of theupwardly curved portions 10 of the lower longronst) and they 17 and theupwardly curved breast portion '20 thereof are provided with the sweepback dippingside edge portions 21 having'the sweep back edges 22 whichmerge at their rear ends with the rear dipping edge portion 18 and thetrailing edge 19, respectively, and which side dipping edge portions 21practically fade away at the leading edge 23 of the airfoil 16, whichisgiven a convexed'camber or curvature, as will be apparent from Fig. 5.Briefly, both the lower airfoil 1 and theupper airfoil, or planes 16 arereversely' curved longitudinally, and transversely curvedand resemblevery much a shoe horn, in plan view, and inverted pans in transvermsectional elevation,

'is provided with a vertically disposed steeras willbe apparent fromFigs. 5 and 2, respectively. As clearly shown in Figs. 2 and 4, theupper-airfoillG has its ear-dipping edge 18 andside dipping edges 1extending beyond the rear dipping edge 4 and side dipping edges 7 of thelower airfoil 1 and has its leading edge'23 disposed shortly to the rearof the leading edge 8 of the lower airfoil 1. In short, the upperairfoil 16'is of greater area than the lowerairfoil and extends over therear and side edges of the lower airfoil 1.

From the foregoing, it will be apparent that airfoils, as described,will cause the displacement of air just as a goose, or as the prow of aboat displaces both air and water, thus creating an upward rising currnt of air. around the dipping side edges 7 of he lower airfoil 1 fordisplacing the vacuum adjacent the upper surface of the lower airfoil 1,incidently densifying the air between the undersurface of the upperairfoil l6 and the upper surface 'of the lower airfoil 1 to establishmaximum stability to the superposed foils -1 and 161 As the aircraftadvances in flight, the

' densified air is further compressed by the enlarged area of the reardipping edge portions 6 of the lower airfoil 1. A similar dynamicpressure is created by the-upper airfoil 16 due to the impact of the airstream flowing between the upper and lower airfoils 1 and 16.

A narrow auxiliary airfoil 24 having a fiat portion 25 is disposedbetween the upper and lower airfoils 1 and '16 at the rear end portionof the" aircraft'and is mounted upon suitable rearward and downwardlycurved longrons 26 which are supported by the rearmost supporting struts12 and braced by the bracing rods 27 which also brace the rear ends ofthe upper longrons 11. This auxiliary airfoil 24 has dipping side edgeportions 28 with the lower edge 29, the dipping rear portion 30 and thetrailing edge 31. The auxiliary airfoil 24 adds further to the liftingof the 1 rear end of the aircraft due -to the impact thereof with theair stream between the upper and lower airfoils 1 and 16 and also addsto the general stability thereof.

To further increase the dynamic pressure,

I employ what I term booster wings which are in the form of twovertically disposed planes These booster wings are hingedly connectedalong their rear edges to certain of the rearmost supportlng struts 12and are adapted to be swung outwardly at any angle desired between theupper and lower airfoils 1 and 16 in advance of the rear ends ofthedipping side edge portions thereof, and their adjusted positions aremade secure by means of the slotted arms 33 which coact with the guidemembers 34 which pass through the slotted arms. The arms are locked tothe guidemembers 34 by suitable fastening devices 35.

The leading or prow end of the aircraft ing vane or rudder shaft 36supported by means of bearing members-37 and 38 and by which shaft therudders 39 and 40 are carried and controlled by a lever 41 through and46 mounted in the bearings 47 and 48,.

which are secured by the forwardmost supporting struts 12. Each pair ofelevators 43 and 44 are connected by means of connecting links 49 whichare pivotally connected at their ends to the elevators. Shaft 45 isprovided with a cross arm 50 and both pairs of elevators are controlledin unison by means of a lever 51 through the medium of two pairs ofspaced parallel arranged connections 52.

The aircraft is supported upon the ground by means of three landingwheels 53, 54 and 55. Wheels 53 and 54 are the rear wheels, and wheel 55is the forward wheel. The wheels are each supported by means of asuitable supporting member 56 associated with .a shock absorbing device57, which includes "extending below the rear and side dipping edges 4and 7 of the lower airfoil 1. The

lower forward edge of the stabilizer 61 is curved upwardly, as at 62,and the leading edge 63 of the stabilizer 61 stops short of the leadingedge 8 of the lower airfoil 1.

The aircraft is driven or pushed by means of a propeller 64 driven bymeans of a suitable motor 65 mounted upon the lower airfoil 1 throughthe medium of the shaft 66,- ineluding a suitable transmission 67 con--trolled by means of a foot pedal 68. v

Forthe purpose of assisting in the landing of the aircraft, I employ ahorizontally disposed lifting propeller 69 which is arranged below therear end portionof the lower airfoil 1 within the bounds of the side and5' rear dipping edge portions thereof. The

driving of this propeller 69 is controlled by the foot pedal andtransmission; When the pedal is pushed down to its forward position, itreleases the propeller 64 from posisweep back to the trailing edges ofthe airfoils, thereby gradually increasing the supporting area so thatthe impact with the air stream becomes gradually greater toward thetrailing edges of the airfoils instead of at I the leading edgesthereof..Thus, it will be seen that the initial lift of the aircraft is due toimpact of the breast portions of the airfoils and then the lift iscompletely estab lished at the trailing ends of the airfoils.

The positive and negative pressure becomes greater at the rear dippingedges of the airfoils due to the impact with the air stream below thelower airfoil and between the superposed airfoils, thus, aiding in thelift and stability of the airfoils. This dynamic action also isincreased due to the fact that the dip ping side edges of the airfoilssweep back from the convexed leading edgesof the airfoils to a widenedarea at the trailing edges thereof.

From the foregoing description, it is evident that a simple device forthis purpose has been disclosed, but it is to be understood. that I donot desire to restrict, or limit my self to the very details of theconstructionshown and described, which is merely illustrative, it beingobvious that changes. not involving-the exerclse of the invention, may

be made without conflicting or departing edge and dipping side edgesvanishing as they approach the leading edges of the airfoils. r

2. In a pusher airplane,superposed airfoils each having a breast portionterininating in a leading edge, a dipping trailing edge and dipping sideedges vanishing as they approach the leading edges of the airfoils, theupper of said airfoils being of a greater area than the lower airfoiL.

3. In a pusher airplane, superposed airfoils each having a breastportion terminating'in a leading edge, a dipping trailing edge anddipping side edges vanishing as they approach the leading edges of theairfoils, the upper of said airfoils being of a greater area than thelower airfoil andhaving its leading edge disposed to the rear of theleadihg edge of the lower airfoil.

4. In a pusher airplane, superposed airfoils each having abreast'portion terminat ing in a leading edge, a dipping trailing edgeand dipping side edges vanishing as they approach the leading edges ofthe airfoils,

the upper of said airfoils being of a greater area than the lowerairfoil and having its leading edge disposed to the rear of the leadingedge of the lower airfoil and vertically disposed movable-booster wingsdisposed he tween the dipping side edges of the airfoils.

ill)

- 5. In a pusher airplane,superposed airfoils each having a breastportion terminating in a leading edge, a dipping trailing edge anddipping side edges vanishing as they approach the leading edges of theairfoils, the upper of said airfoils being of a greater area than'thelower airfoil and having its leading edge disposed to the rear of thelead ing edge of the lower airfoil, vertically disposed movable boosterwings disposed between the dipping side edges of the airfoils and astabilizer depending from the lower airfoil and disposed longitudinallythereof.

6. In a pusher airplane,superposed airfoils each having abreast portionterminating in a leading edge, a dipping trailing edge and dippingside-edges vanishing as they approach the leading edges of the airfoils,the

upper of said airfoils being'of a greater area than the lower airfoiland having its leading edge disposed to tlie rear of the leading edge ofthe lower airfoil, vertically (llS- -posed movable booster,- wingsdisposed between the dipping side edges of the airfoils, a stabilizerdepending from the lower airfoil and disposed longitudinally thereof anda manually actuated rudder disposed in advance of the superposedairfoils.-

7. In a pusher airplane, superposed airfoils each having a breastportion terminating in a leading edge, a dipping trailing edge anddipping side edges vanishing as they approach the leading edges of theairfoils, the upper of said airfoils being of a greaterv area. than thelower airfoil and having its leading edge disposed to the rear of theleading edge of the lower airfoil, vertically disposed movable boosterwings disposed between the dipllll) ping side edges of the airfoils, astabilizer depending from the lower airfoil and disposed longitudinallythereof, a manually actuated rudder disposed in advance of thesuperposed airfoils and manually actuated superposed elevators disposedbetween the breast portions of said airfoils.

8. In a pusher airplane, superposed airfoils each having a breastportion terminating in a leading edge, a dipping trailing edge anddipping side edges vanishing as they approach the leading edges of theairfoils,

the upper of said airfoils being of a greater a lower airfoil of smallerarea, an auxiliary area than the lower airfoil and having its leadingedge disposed to the rear of the leading edge of the lower, airfoil,vertically disposed movable booster wings disposed between the dippingside edges of the airfoils, a stabilizer depending from the lowerairfoil and disposed longitudinally thereof, a manually actuated rudderdisposed in ad- Vance of the superposed airfoils, manually actuatedsuperposed elevators disposed between the breast portions of saidairfoils, a power plant mounted upon the lower airfoil, and a propellerdisposed below the dipping trailing edge of 'the upper airfoil and tothe rear of the trailing edge of the lower airfoil.

9. In a pusher airplane, superposed airfoils each having a breastportion terminating in a leading edge, a dipping trailing edge anddipping side edges vanishing as theyapproach the leading edges of theair-,.

foils, the upper of said airfoils being of a greater area than the lowerairfoil and hav ing its leadin edge disposed to the rear of the leadinge ge of the lower airfoil, vertically disposed movable booster wings disposed between the dippingside edges of the airfoils, a stabilizerdepending from the lower airfoil and disposed longitudinally thereof, amanually actuated rudder disposed in advance of the superposed airfoils,manually actuated superposed elevators disposed between the breastportions of said airfoils,

a power-plant mounted upon the lower airfoil, a propeller disposed belowthe dipping trailing edge of the upper airfoil and to the rear of thetrailing edge of the lower airfoil and a vertically disposedlandingpropel-ler disposed below the trailing end of the lower airfoil.

10. In a pusher airplane, superposed airfoils each having a breastportion terminating in a leading edge, a dipping trailing edge anddipping side edges vanishing as they approach the leading edges of theairfoils, the upper of said airfoils being of a greater area than thelower airfoil and having its leading edge disposed to the rear of theleading edge of the lower airfoil, vertically disposed movable boosterwings disposed between the dipping side edges of the airfoils, astabilizer depending from the lower airfoil and, disposed longitudinallymaaeea thereof, a manually actuated rudder disposed a verticallydisposed landing propeller disposed below the trailing end of the lowerair-- gear upon foil and a three wheel landing which the lower airfoilis mounted.

11. In a pusher airplane, an upper airfoil,

airfoil of relatively small area, said. upper and lower airfoils havingcurved breast portions terminating in leading edges, dipping trailingedges and sweep back dipping side edges and said' auxiliary airfoilhaving dipping side edges terminating in a dipping trailing edge.

. 12. In a pusher airplane, an upper airfoil, a lower airfoil of smallerarea, an auxiliary airfoil of. relatively small area, said upper andlower airfoils having curvedbreast portions terminating in leadingedges, dipping trailing edges and sweep back dipping side edges, saidauxiliary airfoil having dipping side edges terminating in a dippingtrailing edge and vertically disposed hingedly supported booster wingsdisposed between the clipping sideedges of the upper and lower airfoils.

13. In a pusher airplane, upper foils and lower airfoils, said airfoilseach having a narrow convexed trailing edge, upwardly curved breast,portions, sweep back dipping side edges terminating in convexed dippingtrailing edges whereby to form airfoils substantially cone shaped inplan view.

14..In an aircraft structure, in combination, a lower airfoil, an upperairfoil, a power plant mounted on said lower airfoil, a propelleradjacent the rear ends of the airfoils and disposed below the upperairfoil, a vertical rudder in advance of both airfoils, an elevatordisposed between the uppending from the lower airfoil and disposedlongitudinally thereof.

15. In an aircraft structure in combination, a lower airfoil, an upperairfoil, a power plant mounted on said .lower airfoil, a ro-' p'elleradjacent the rear ends of the air oils and disposed below the trailingedge of the upper airfoil and to the rear of the lower airfoil,aWertical rudder in advance of both airfoils, an elevator disposedbetween the upper and lower airfoils at the forward ends thereof and astabilizer having its lower edge convexed at its forward end dependingfrom the lower airfoil and disposed longitudinally thereof.

16. In an aircraft structure, in combination, superposed airfoils havingsweep back iliary airfoil, a stabilizer depending from the.

lower of said superposed alrfoils, a vertical rudder supported .111advance of said airfolls,

' means for actuating said rudder, superposed elevators disposed betweenthe forward u wardly curved ends of said airfoils, means for actuatingsaid elevators in unison, a power plant mountedupon the lower of saidsuperposed airfoil, a propeller driven by said power plant and disposedso as to push the aircraft, a three wheel landing gear and a landingpropeller disposed below the rear portion of the lower of saidsuperposed airfoils and propelled by said power plane when the firstmentioned propeller has ceased rotation under power.

- 17. In an aircraft structure, a top airfoil having a long sweep backchord, a short leading edge span and a longer trailing edge span thanthe leading edge span, a lower airfoil having a long sweep back chord, ashort leading edge span and a longer trailing edge span than the leadingedge span and suspended from the top airfoil, an auxiliary airfoildisposed between the top and lower airfoils at the rear ends thereof, apower plant in advance of the auxiliary airfoil and supported by thelower airfoil, a vertical rudder-in advance of said top and lowerairfoils, elevators disposed between the top and lower airfoils, a threewheel landing gear, a pusher propeller driven by said power plant and ahorizontally disposed landing-propeller b.c' low said lower airfoildriven by said power plant when the pusher propeller has ceased rotationunder power.

In testimony whereof, I have hereunto affixed my signature.

CARL G. THoMPsoN.

